Consider a wave approaching a barrier with a small hole. What change is the wave likely to undergo as it encounters the barrier?

Question

anonymous · Answer

Depending on how small the hole is, the wave could be disturbed to the point of diffraction. That is, it could start to radiate outward on the other side of the hole, and create an interference pattern on the other side (if there is a viewing screen, or something of that nature).

This is actually a fairly famous phenomenon. If you'd like to know details about it, you should look for the "single slit" and "double slit" experiments!